The present invention relates to detonation arrestors for use in chemical processing and handling industries.
Chemical and pipeline industries pump flammable and detonatable gaseous mixtures between and within plants through pipes either intentionally, during normal operations or accidentally, during upset conditions. Under these circumstances accidental ignition of the combustible mixture can cause an explosion. An explosion may be contained by the piping and vessels of the system, but more often causes catastrophic rupture of portions of the system with attendant injury or loss of life, damage to the plant and costly business interruption.
Industry has attempted to control or prevent these ruptures by installing either vents or arrestors. Vents are designed to open rapidly when the local internal pressure rises above some preset value. These vents usually contain prescored sheet metal diaphragms. However, vents are ineffective when the burning rates are high, such as in the case of very fast deflagration or detonation propagation. While deflagrations are easy to quench with flame arrestors, detonations are extremely difficult to quench.
To arrest detonations, a series of detonation arrestors, or a combination of a single detonation arrestor with a pair of flame arrestors may be used. The arrestors are installed at strategic locations in the piping. Though the currently known arrestors are effective under certain conditions, they always create a high pressure drop in the line where they are installed. Thus, processing costs are increased because the cost of pumping the gases through the system are increased.
A swirl type detonation arrestor which does not create as high a pressure drop as the arrestors discussed above, has also been employed. This device, however, is effective only for one direction of detonation propagation.
An effective detonation arrestor system or arrangement which would not cause a high pressure drop in a line would be very desirable and widely accepted by those skilled in the art. If such an arrestor was effective in either direction of detonation propagation, it would be additionally welcomed by the industry.
It is therefore an object of the present invention to provide a low pressure drop detonation arrestor for use in chemical processing and handling systems. A further object is to provide a detonation arrestor which will cause a detonation to fail regardless of the direction of detonation propagation. A still further object of the present invention is to provide a detonation arrestor arrangement which, after causing a detonation to fail, will also extinguish the resulting flame, thus preventing any flame that is present to be accelerated to detonation.
Other objects of the present invention will be apparent to those skilled in the art in view of the following description and are therefore also contemplated. Objectives, however, are not to be considered a limitation of the present invention, the scope of which is defined by the appended claims.